1. Field of the Invention
The present invention relates to a method and apparatus for ascertaining the permeability of core specimens, and more particularly to a method and apparatus for simultaneously testing multiple core specimens.
2. Description of the Related Art
The permeability of a material, such as soil or rock, is a very important parameter to a foundation engineer. A material is said to be permeable if it contains continuous voids. All soils and rocks are permeable; however, there are vast differences in the degree of permeability of various earth materials. The measurement of permeability of a soil or rock indicates how fast a fluid will flow through the given material.
Depending on the type of soil that is being tested, a permeability test may last as long as several days and even a few weeks. Prior art permeability testing devices are capable of performing only one permeability test on one core specimen at a time. Permeability tests often need to be performed on several core specimens in a relatively short period of time. Due to the fact that each test may last several days, either several permeability testers must be utilized or a prolonged period of time is required to test all of the soil specimens.
In U.S. Pat. No. 4,573,342 to Jones, a permeability testing apparatus including a carousel capable of carrying a plurality of core specimens is disclosed. The apparatus automatically determines the permeability for a plurality of core specimens; however, only one specimen is tested at a time. When the test on one core specimen is completed, the apparatus automatically rotates the carousel to the next core specimen until all of the core specimens have been individually tested. This apparatus affords little, if any, time saving over sequentially testing individual specimens in a sequence.
It would be desirable to have a permeability testing device capable of simultaneously testing multiple core specimens. It would also be desirable to be able to start and/or finish the permeability test on a core specimen independently of other ongoing permeability tests. It would further be desirable to be able to conduct simultaneous permeability tests on a plurality of core specimens at more than a single pressure.